Mechanical pipe bender



y 21, 1964 c. 1.. FLESSATE ETAL 3,141,494

MECHANICAL PIPE BENDER 2 Sheets-Sheet 1 Filed Aug. 24, 1960 FIG! \ m .A I v.

INVENTOR5 6, $5M BY C. $220M, WZWLQZ ATTORNEYS,

y 1964 c. L. FLESSATE ETAL 3,141,494

MECHANICAL PIPE BENDER Filed Aug. 24, 1960 2 Sheets-Sheet 2 IN VEN TOR5 ATTORNEYS United States Patent 3,141,494 MECHANICAL PIPE BENDER Clarence L. Fiessate, Waukesha, and Charles G. Pahl,

Milwaukee, Wis, assignors to Applied Power Industries, lnc., a corporation of Wisconsin Filed Aug. 24, 1960, Ser. No. 51,651 4 (Ilairns. (Cl. 15340) The present invention relates generally to improvements in the art of bending elongated articles such as pipe, rods or tubing and it relates more particularly to improvements in the construction and operation of mechanically actuated pipe benders.

The primary object of the present invention is to provide an improved mechanically actuated pipe bender which is simple and inexpensive in construction and highly versatile, flexible and efiicient in actual use.

Various types of pipe bending machines have heretofor been proposed. One of these prior machines embodies generally a frame having a bending shoe pivotally mounted thereon and mechanically actuated by means of a rachet mechanism, the pipe being fed to the bending shoe from a stationary support performing the function of a reaction block during the bending operation as the shoe is pivotally swung about its pivot.

While this type of device has enjoyed some degree of commercial success, the use thereof has been unnecessarily limited for various reasons. For one thing, these prior mechanically actuated bending devices did not have provision for interchanging shoes of different sizes to accommodate pipes or tubing of diverse diameters and it was necessary to extensively dismantle and reassemble the frame, especially the supporting structure for the shoes, When operating upon conduit of diverse sizes and in performing bends of different radius. Furthermore, no means were provided in these prior machines for automatically arresting swinging movement of the shoe at a predetermined position so as to insure uniformity in the magnitude of the bend on successive articles. In addition, the prior mechanically actuated devices of this general type were unnecessarily limited in use to pipes or tubing possessing certain characteristics and were not sufiiciently flexible in their adaptations to meet all requirements. Also, these prior benders were bulky and not readily transportable to different localities and Were unnecessarily confined in their operation due to the inability to readily interchange the bending shoes.

It is therefore an important object of this invention to provide an improved mechanically actuated pipe bender which obviates all of the aforesaid disadvantages of these prior devices.

Another object of the invention is to provide a mechanically actuated pipe bender in which provision is made for readily interchanging bending shoes of diiferent radius and sizes to accommodate pipes of diverse daimeters without need for dismantling the frame, the guide means or reaction block being adjustable in height to accommodate the different shoes.

Another object of the invention is to provide a pipe bending device having adjustable means for definitely arresting the swinging movement of the bending shoe at a predetermined position so as to enable rapid and uniform production of bends on successive articles of identical curvature and/or magnitude.

Another object of our invention is to provide a manually operable conduit bender which can be manufactured and sold at relatively low cost and which is highly flexible and versatile in operating on pipes or tubing of various different characteristics and in which interchangeable reaction blocks are carried on a common support and can be selectively swung into operative position.

3,141,494 Patented July 21, 1964 retained on its shaft in a simple manner by means of an angle gauge which also performs the function of measuring the angle or magnitude of bend.

These and other objects or advantages of the invention will be apparent from the following detailed description.

A clear conception of the features constituting the present improvement and of the construction and operation of a typical pipe bender embodying the invention may be had by referring to the drawings accompanying and forming a part of this specification wherein like reference characters designate the same or similar parts in the various views.

FIGURE 1 is a fragmentary side elevation of a commercial mechanical pipe bender, showing the parts thereof in solid lines while in starting posion and in dot-anddash lines upon completion of a bend and with portions broken away in order to reveal normally hidden structure;

FIGURE 2 is an end view of the same machine looking toward the right of the assemblage and as shown in solid lines in FIGURE 1;

FIGURE 3 is a further enlarged fragmentary view of the bend gauge; and

FIGURE 4 is a considerably reduced perspective view of a similar pipe bending unit, but which is adapted to bend three sizes of conduits of different cross-section instead of only two as in FIGURES 1 and 2.

While the invention has been shown and described herein as having been embodied in a portable manually actuated ratchet type pipe bender, some of the improved features are susceptible of more general application to other types; and it is also contemplated that specific descriptive terms employed herein be given the broadest possible interpretation consistent with the disclosure.

Referring to the drawing, the portable pipe bender shown therein, comprises in general, a sturdy skeleton frame having a T-shaped base beam 6 provided at one end with a pair of transporting wheels 7 and at its medial portion with an upright stop rod 8 and with front and rear upstanding polygonal sectioned columns 9, 10 respectively: a quadrant bending shoe 11 oscillatably suspended from a stub shaft 12 firmly secured to the upper extremity of a backplate 10 of the frame which is rigidly attached to the columns 9, 10, this shoe having several arcuate peripheral grooves 13, 14 and an arcuate internal set of ratchet teeth 15; a conduit jaw 16 secured to the front end of the shoe 11 and being cooperable with the grooves 13, 14 to confine lengths of conduit or pipe 17 therein; a duplex conduit support 18 adjustably associated with the rear column 10 for guiding the leading end of a pipe 17 into the clamping jaw 16; and a free swinging ratchet pawl 19 carried by an arm 20 which is pivotally attached to the frame backplate 10' by a pivot pin 21 and is adapted to be manipulated with a handle 22 in order to swing the shoe 11 from starting position as shown in solid lines into final bending position as shown in dot-and-dash lines in FIGURE 1.

The main frame may be formed primarily from structural steel, and the transporting wheels are mounted on a journal shaft 24 which is elevated relative to the base beam 6 sufficiently high so that this beam will rest upon a floor or other support when the unit is in use, but the wheels 7 may be utilized for transportation purposes when the bender is tilted bodily to bring them into rolling engagement with the floor. The rod 8 may be formed of solid stock and has its lower end firmly attached to the beam 6 while its upper portion is provided with a vertically adjustable stop collar 25 with which the front edge of the shoe 11 is engageable to limit its upward or forward swing and to thereby control the length of the bend being produced in the pipe 17. The front column 9 also has its lower end firmly secured to the base beam 6 while the pivot shaft 12 is rigidly attached to its upper end, and its medial portion beneath the shaft 12 is provided with a rotary stop 26 for positioning the shoe for the initial reception of a pipe 17.

The quadrant shoe 11 is preferably formed of a durable casting accurately machined to cause the arcuate grooves 13,14 and the arcuate set of ratchet teeth 15 thereof to swing about the axis of the stub shaft 12, and

this shoe is readily removable from the pivot shaft 12 and may be provided with one or more of the arcuate pipe confining grooves. As illustrated in FIGURES 1 and 2, the shoe 11 has two arcuate grooves 13, 14 of which the groove 13 has a longer radius of curvature and is adapted to receive pipe 17 of larger diameter, than the groove 14. In FIGURE 4 the bending shoe 11 is provided with an additional arcuate groove 28 having a shorter radius of curvature than thatof the groove 14, and these double and triple grooved shoes 11 may be interchangeably applied to the stub shaft 12 when bending conduits 17 of different diameters 'to curvatures of diverse magnitude radii.

The clamping jaw 16 which is carried by and swingable with the shoe 11 and cooperates with the grooves 13, 14 to confine the successive pipes 17 therein, is also formed of durable metal and of U-shape as shown in FIGURE 2, and this retaining jaw should be detachably secured to the quadrant shoe 11 and provided with arcuate notches 30, 31 formed to cooperate with pipes 17 confined within the adjacent grooves 13, 14 respectively. The duplex conduit support 18 comprises an inclined arm having a polygonal lower portion 32 embracing and slidably adjustable along the rear column and an upper laterally extending portion 33; and several. guiding members 34, 35 swingably suspended from the lateral portion 33 by a pivot pin 36, as illustrated in FIGURE 1. The lower portion 32 of the support 18 is cooperable with spaced teeth 37 secured to the column 10 to vary the elevation of the upper portion 33 and is adapted to be held in adjusted position by a latch 38, and the members 34, 35 which are recessed to cooperate with the grooves 13, 14 respectively of the shoe 11, may be alternately swung about the pivot pin 36 into active or inactive position as will be apparent from FIGURE 1. The polygonal formation of the column 10 and of the support portion 32 prevents the latter from turning about the column.

The ratchet pawl 19 is swingably secured to the arm 21% by a pivot 40 and is constantly urged toward the ratchet teeth by a torsion spring, not shown. The pivot 49 coacts with the pawl 19 so that the latter may be retracted from the teeth 15 by means of a cable 41 and a rod 42 slidably secured to the arm 20, see FIG- URE 1. The manipulating handle 22 may be a piece of standard rod or pipe stock of any desired length adapted to be inserted within a socket in the outer end of the arm 20, and in order to predetermine and gauge the length of the bends which are to be applied to the conduits, the hub of the quadrant shoe 11 is provided with a pointer 44 which is cooperable with a bend indicator gauge plate 45 carried by the front column 9 and which also coacts with an annular groove in the shoe and serves to detac hably retain the shoe 11 upon its pivot shaft 12, see FIGURE 3. In order to adapt the pipe bender to produce bends a different radii, the pivot pin 21 may be mounted in the backplate 10' in several locations. For small radius bends, this pivot pin 21 together with the ratchet lever 21) is moved from the position shown in FIGURE 1, to the hole 46 which is threaded to receive this pin.

When the various parts of the bender have been constructed as above described, a shoe 11 having grooves 13, 14, 28 of proper curvature and cross-section to perform the contemplated work should first be selected from several furnished with the unit, and this quadrant shoe should then be applied and latched to the pivot shaft 12 with the aid of the gauge plate 45. When required, the proper pipe guiding member 34, 35 corresponding to the selected shoe groove 13, 14 should be positioned upon the upper portion 33 of the support 18 and the latter should be adjusted along the column 10 so as to properly position the upper recess of the selected member 34, 35 in horizontal alignment with the selected groove of the shoe 11. The rod 42 should then be manipulated to swing the pawl 19 out of engagement with the ratchet teeth 15, after which the shoe 11 with the jaw 16 attached may be swung manually in a counterclockwise direction until it engages the stop 26 in starting position. The stop collar 25 should then be adjusted along the rod 8 to produce a bend of desired magnitude.

With the unit thus pre-conditioned and adjusted, successive conduits or pipes 17 may be inserted endwise along the groove of the active supporting member 34, 35 and threaded into the horizontally aligned opening provided by the selected groove 13, 14 of the shoe 11 and the corresponding recess 30, 31 of the jaw 16, until the leading end of the inserted pipe reaches the position shown in solid lines in FIGURE 1. The shoe 11 may then be swung in a clockwise direction about its pivot shaft 12 with the aid of the handle and the ratchet pawl 19 coacting with the ratchet teeth 15 until the shoe engages the stop collar 25 and the pointer 44 coacting with the gauge plate 45 will visibly disclose the exact magnitude of the bend. Because of the resiliency of some conduits or pipes 17 it is advisable to slightly overbend such pipes so that the final product will be bent precisely to the desired extent.

By providing a proper array of shoes 11, jaws 16 and guide members, the single unit may be utilized to effectively bend conduits or pipes 17 of different diameter and wall thickness through arcs or bends of any desired magnitude with utmost precision regardless of the material from which the pipes are formed. The various adjustment provided makes it possible to change from one type of production to another with minimum loss of time, and the power required to effect the bending operations may also be conveniently varied. The unit may also be readily transported with the aid of the wheels 7, but the T-beam provides a firm retaining base for preventing shifting while pipes are being bent. Loose parts such as the jaw 16, latch 38 and gauge plate 45 may be attached to the frame with the aid of chains or cables, and the handle 22 may be stored within the box beam 6 of the frame when not in use. The invention has gone into highly satisfactory commercial use, and the improved relatively simple unit is obviously exceedingly flexible in its adaptations.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

We claim:

1. A conduit bender comprising, a frame, a pipe bending shoe pivotally suspended from said frame and having therein an arcuate pipe bending groove, means for guiding a pipe longitudinally into the groove, means for holding the leading-end of the pipe within said groove, means for swinging the shoe to bend the retained pipe, and a gauge slidably received by said frame laterally adjacent said shoe for visually indicating the extent to which the pipe has been bent, said gauge having an edge portion coacting with said bending shoe to retain the same against displacement on its pivot.

2. A conduit bender according to claim 1, wherein 5 the bending shoe has a hub portion provided with an annular groove and the shoe retaining edge portion of the gauge is of arcuate shape receivable within the groove of said hub portion.

3. A conduit bender comprising, a frame, a pipe bending shoe swingably suspended from said frame and having therein several independent arcuate pipe bending grooves, a pipe guiding support carried by said frame and being adjustable toward and away from said shoe, a plurality of independent arcuately grooved guides swingably mounted upon said support and selectively swingable into and out of pipe guiding position whereby the grooves thereof alternately cooperate with selected grooves of said shoe to guide pipes of diiferent diameters longitudinally to said shoe, a retainer jaw for holding the end of the pipe within the selected groove, and means for swinging said shoe to bend the held pipe.

4. A conduit bender according to claim 3, wherein the pipe guiding support is laterally offset from the axis of the swingable shoe and is vertically adjustable on the frame.

References Cited in the file of this patent UNITED STATES PATENTS 807,854 Neuert Dec. 19, 1905 1,676,263 Hawkins July 10, 1928 1,849,181 Francis Mar. 15, 1932 1,899,281 Lidseen Feb. 28, 1933 2,455,138 Perkins Nov. 30, 1948 2,537,254 Blythe Jan. 9, 1951 2,762,415 Franck Sept. 11, 1956 2,819,752 Hart Jan. 14, 1958 2,979,102 Ferguson et a1. Apr. 11, 1961 3,020,015 Seplavy Feb. 6, 1962 

1. A CONDUIT BENDER COMPRISING, A FRAME, A PIPE BENDING SHOE PIVOTALLY SUSPENDED FROM SAID FRAME AND HAVING THEREIN AN ARCUATE PIPE BENDING GROOVE, MEANS FOR GUIDING A PIPE LONGITUDINALLY INTO THE GROOVE, MEANS FOR HOLDING THE LEADING END OF THE PIPE WITHIN SAID GROOVE, MEANS FOR SWINGING THE SHOE TO BEND THE RETAINED PIPE, AND A GAUGE SLIDABLY RECEIVED BY SAID FRAME LATERALLY ADJACENT SAID SHOE FOR VISUALLY INDICATING THE EXTENT TO WHICH THE PIPE HAS BEEN BENT, SAID GAUGE HAVING AN EDGE PORTION COACTING WITH SAID BENDING SHOE TO RETAIN THE SAME AGAINST DISPLACEMENT ON ITS PIVOT. 